docs: def download_uniprot_file(uniprot_id, filetype, outdir='', force_rerun=False):
      """Download a UniProt file for a UniProt ID/ACC
  
      Args:
          uniprot_id: Valid UniProt ID
          filetype: txt, fasta, xml, rdf, or gff
          outdir: Directory to download the file
  
      Returns:
          str: Absolute path to file
  
      """
  
      my_file = '{}.{}'.format(uniprot_id, filetype)
      url = 'http://www.uniprot.org/uniprot/{}'.format(my_file)
      outfile = op.join(outdir, my_file)
  
      if ssbio.utils.force_rerun(flag=force_rerun, outfile=outfile):
          urlretrieve(url, outfile)
  
      return outfile